U.S. patent number 10,214,659 [Application Number 15/467,326] was granted by the patent office on 2019-02-26 for aqueous compositions having polyalkoxylates for improved open time.
This patent grant is currently assigned to Dow Global Technologies LLC. The grantee listed for this patent is Dow Global Technologies LLC. Invention is credited to Sudhakar Balijepalli.
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United States Patent |
10,214,659 |
Balijepalli |
February 26, 2019 |
Aqueous compositions having polyalkoxylates for improved open
time
Abstract
The present invention provides aqueous compositions that provide
improved open time, the compositions comprising (i) an aqueous
polymer composition of one or more emulsion polymers, one or more
aqueous dispersion polymers, or mixtures thereof, preferably, a
vinyl or acrylic emulsion polymer, and (ii) from 0.1 to 5 wt. %,
based on the total weight of solids in the composition, one or more
polyalkoxylates having from 2 to 15 polyalkoxylate chains and an
ethylene oxide (EO) content ranging from 20 to 70 wt. %, based on
the total weight of polyalkoxylate solids in the composition. The
compositions are useful in high solids or fast drying compositions
such as coatings and non-cementitious mortars.
Inventors: |
Balijepalli; Sudhakar (Midland,
MI) |
Applicant: |
Name |
City |
State |
Country |
Type |
Dow Global Technologies LLC |
Midland |
MI |
US |
|
|
Assignee: |
Dow Global Technologies LLC
(Midland, MI)
|
Family
ID: |
58489484 |
Appl.
No.: |
15/467,326 |
Filed: |
March 23, 2017 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20170275490 A1 |
Sep 28, 2017 |
|
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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62314024 |
Mar 28, 2016 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C09D
7/63 (20180101); C09D 7/65 (20180101); C09D
133/12 (20130101); C09D 5/02 (20130101); C09D
5/00 (20130101); C08L 33/06 (20130101); C09D
7/61 (20180101); C08L 33/06 (20130101); C08L
71/02 (20130101); C08L 2201/52 (20130101); C08K
13/02 (20130101) |
Current International
Class: |
C08L
33/06 (20060101); C09D 133/12 (20060101); C09D
5/00 (20060101); C09D 7/61 (20180101); C09D
7/63 (20180101); C09D 7/65 (20180101); C09D
5/02 (20060101); C08K 13/02 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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1340792 |
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Sep 2003 |
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EP |
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2457960 |
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May 2012 |
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EP |
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02097159 |
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Dec 2002 |
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WO |
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2011158102 |
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Dec 2011 |
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WO |
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2014058864 |
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Apr 2014 |
|
WO |
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2014099821 |
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Jun 2014 |
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WO |
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Other References
Non-Final Office Action for U.S. Appl. No. 15/467,059; dated Feb.
27, 2018; 8 pages. cited by applicant.
|
Primary Examiner: Pak; Hannah J
Attorney, Agent or Firm: Stauss; Karl E. Cantor Colburn
LLP
Claims
I claim:
1. An aqueous composition comprising: (i) an aqueous polymer
composition of one or more emulsion polymers, one or more aqueous
dispersion polymers, or mixtures thereof, and (ii) from 0.1 to 5
wt. %, based on the total weight of solids in the aqueous
composition, one or more polyalkoxylates having from 2 to 15
polyalkoxylate chains and an ethylene oxide (EO) content ranging
from 20 to 70 wt. %, based on the total weight of polyalkoxylate
solids in the aqueous composition.
2. The aqueous composition as claimed in claim 1, wherein the (i)
aqueous polymer composition is one or more vinyl or acrylic
emulsion polymers.
3. The aqueous composition as claimed in claim 2, wherein at least
one of the (i) one or more vinyl or acrylic emulsion polymers has a
measured (DSC) glass transition temperature (measured T.sub.g) of
from -100 to 20.degree. C.
4. The aqueous composition as claimed in claim 1, wherein the (ii)
one or more polyalkoxylates has the formula, I-[AO.sub.nH].sub.f,
wherein I is an organic active hydrogen containing compound;
wherein AO is an alkylene oxide that comprises ethylene oxide (EO)
or EO combined with propylene oxide (PO) and/or butylene oxide (BO)
in a random order or in an oligomer having blocks; wherein n is the
total number of AO groups and may range from 1 to 50, and f ranges
from 2 to 15.
5. The aqueous composition as claimed in claim 4, wherein in the
formula I-[AO.sub.nH].sub.f, f ranges from 3 to 8.
6. The aqueous composition as claimed in claim 1, wherein at least
one of the (ii) one or more polyalkoxylates has a normal boiling
point at 100 kPa of from 280.degree. C. to 450.degree. C.
7. The aqueous composition as claimed in claim 1, wherein the (ii)
one or more polyalkoxylates is a polyalkoxylate of an active
hydrogen compound chosen from polyols having 3 or more hydroxyl
groups, difunctional aminoalcohols, diamines, triamines,
polyamines, and phenolic resins having 3 to 8 hydroxyl groups.
8. The aqueous composition as claimed in claim 7, wherein the (ii)
one or more polyalkoxylates is a polyalkoxylate of diethanol amine,
glycerol, pentaerythritol, a sugar alcohol, a diamine or a
triamine.
9. The aqueous composition as claimed in claim 1, wherein the
aqueous composition further comprises one or more coalescents with
a normal boiling point of from 280.degree. C. to 450.degree. C.
10. The aqueous composition as claimed in claim 1, further
comprising one or more fillers, extenders and/or pigments, or one
or more pigments combined with one or more fillers and/or
extenders.
11. The aqueous composition as claimed in claim 4, wherein AO is an
alkylene oxide that comprises ethylene oxide (EO) or EO combined
with propylene oxide (PO) and/or butylene oxide (BO) in an oligomer
having at least one block of EO.
12. The aqueous composition as claimed in claim 1, wherein the (ii)
one or more polyalkoxylates has a number average molecular weight
(M.sub.n) of from 800 to 10,000.
13. The aqueous composition as claimed in claim 1, wherein the
aqueous composition is an aqueous coating composition.
14. The aqueous composition as claimed in claim 1, wherein the
aqueous composition is a non-cementitious binder composition for
waterproofing membranes or EIFS topcoats.
Description
The present invention relates to aqueous compositions that comprise
(i) aqueous polymer compositions, such as one or more emulsion
polymers or aqueous dispersion polymers, and from 0.1 to 5 or,
preferably, up to 2.0 wt. %, based on the total weight of solids in
the composition, of (ii) one or more polyalkoxylates having from 2
to 15 polyalkoxylate chains and an ethylene oxide (EO) content
ranging from 20 to 70 wt. %, based on the total weight of
polyalkoxylate solids in the composition. More particularly, it
relates to low volatile organic content (VOC) aqueous compositions
comprising (i) one or more emulsion polymers, aqueous dispersion
polymers or mixtures thereof and (ii) from 0.1 to 5 wt. % or,
preferably, up to 2.0 wt. %, based on the total weight of solids in
the composition, of one or more polyalkoxylates of the formula
I-[AO.sub.nH].sub.f, wherein I is an organic active hydrogen
containing compound; wherein AO is an alkylene oxide that comprises
ethylene oxide (EO) or EO combined with propylene oxide (PO) and/or
butylene oxide (BO) in a random order or in an oligomer having
blocks, preferably, having at least one block of EO; wherein n is
the total number of AO groups and may range from 1 to 50, or,
preferably, from 2 to 20; and, wherein f is the total number of
active hydrogen groups in I, which ranges from 2 to 15.
Waterborne or aqueous coating compositions have recently been
developed with lower amounts of volatile organic compounds (VOCs),
such as below 150 g/L. The aqueous compositions may comprise
emulsion polymers having a measured (DSC) glass-transition
temperature (Tg) of from -50 to 30.degree. C., and rely on the
addition of VOCs as coalescing agents to enable film formation at
ambient temperature and subsequent curing. The presence of VOCs in
an aqueous paint or coating composition formulation also imparts
better open time and freeze-thaw (F/T) stability, as well as
enables better flow and leveling, substrate wetting and paint film
defoaming, which can lead to better adhesion and surface appearance
properties. A number of these properties are compromised as the
market moves to low/zero VOC coatings with low T.sub.g zero VOC
binders due to fast film formation. Therefore there is market
demand for aqueous paint or coating compositions having
significantly improved open time and/or wet edge time during
application.
U.S. patent publication no. US2014/0256862A1, to Palmer Jr., et al.
discloses aqueous compositions for use in coatings, alkyd paints
and paper coating compositions the compositions comprising
alkoxylates of tri- or di-styrenated phenols and ethylene
oxide/propylene oxide surfactants, wherein open time or freeze thaw
properties are imparted to the composition. Further, such
alkoxylates if converted to the sulfate or phosphate anion can
provide improved open time.
Accordingly, the present inventors have sought to solve the problem
of providing excellent open time properties of aqueous compositions
for use as coatings paints, especially high solids and elastomeric
polymer compositions.
SUMMARY OF THE INVENTION
1. In accordance with the present invention, aqueous compositions
comprise (i) an aqueous polymer composition of one or more emulsion
polymers, one or more aqueous dispersion polymers, or mixtures
thereof, and (ii) from 0.1 to 5 wt. %, or, preferably, up to 2.0
wt. %, based on the total weight of solids in the composition, one
or more polyalkoxylates having from 2 to 15 or, preferably, from 3
to 10, or, more preferably, from 3 to 8 polyalkoxylate chains and
an ethylene oxide (EO) content ranging from 20 to 70 wt. %, or,
preferably, from 20 to 50 wt. %, based on the total weight of
polyalkoxylate solids in the composition.
2. In accordance with the aqueous compositions of the present
invention as in item 1, above, wherein the (i) aqueous polymer
composition comprises one or more emulsion polymers comprises one
or more vinyl or acrylic emulsion polymers, preferably, at least
one vinyl or acrylic emulsion polymer having a measured (DSC) glass
transition temperature (measured Tg) of from -100 to 20.degree. C.
or, preferably, from -60 to 15.degree. C., such as, for example, an
elastomeric emulsion polymer.
3. In accordance with the aqueous compositions of the present
invention in any one of items 1 or 2, above, wherein the (i)
aqueous polymer composition comprises one or more emulsion polymers
containing, in copolymerized form, one or more monomers chosen from
C.sub.1 to C.sub.24 alkyl acrylates or C.sub.1 to C.sub.24 alkyl
methacrylates, vinyl esters, vinyl aromatics, such as styrene.
Preferably, (i) the aqueous polymer compositions comprise one or
more vinyl or acrylic emulsion polymers. More preferably, the vinyl
or acrylic emulsion polymers additionally comprise, in
copolymerized form, one or more monomer chosen from ethylenically
unsaturated carboxylic acid monomers, like (meth)acrylic acid or
its salts; ethylenically unsaturated amide monomers, such as
acrylamides; phosphorus acid group containing vinyl or acrylic
monomers, such as phosphoethyl methacrylate; sulfur acid group
containing vinyl or acrylic monomers, such as methacrylamidopropane
sulfonic acid or its salts; multiethylenically unsaturated
monomers, such as allyl methacrylate; hydroxy-functional monomers;
amine-functional monomers; epoxy-functional monomers;
keto-functional monomers, and autooxidizable monomers.
4. In accordance with the aqueous compositions of the present
invention as in any one of items 1, 2, or 3, above, wherein the
(ii) one or more polyalkoxylates has the formula
I-[AO.sub.nH].sub.f, wherein I is an organic active hydrogen
containing compound; wherein AO is an alkylene oxide that comprises
ethylene oxide (EO) or EO combined with propylene oxide (PO) and/or
butylene oxide (BO) in a random order or in an oligomer having
blocks, preferably, having at least one block of EO; wherein n is
the total number of AO groups and may range from 1 to 50, or,
preferably, from 2 to 20; and, wherein f is the total number of
active hydrogen groups in I, which ranges from 2 to 15 or,
preferably, from 3 to 10, or, more preferably, from 3 to 8.
5. In accordance with the aqueous compositions of the present
invention as in any one of items 1, 2, 3, or 4, above, wherein the
(ii) one or more polyalkoxylates has a number average molecular
weight (Mn) of from 800 to 10,000 or, preferably, from 800 to
6000.
6. In accordance with the aqueous compositions of the present
invention as in any one of items 1, 2, 3, 4, or 5, above, wherein
at least one of the (ii) one or more polyalkoxylates has a normal
boiling point at 100 kPa of from 280.degree. C. to 450.degree. C.
or, preferably, 300.degree. C. or higher.
7. In accordance with the aqueous compositions of the present
invention as in any one of items 1, 2, 3, 4, 5, or 6, above,
wherein the (ii) one or more polyalkoxylates is a polyalkoxylate of
an active hydrogen compound chosen from polyols having 3 or more
hydroxyl groups, difunctional aminoalcohols, diamines, triamines,
polyamines, and phenolic resins having 3 to 8 hydroxyl groups.
8. In accordance with the aqueous compositions of the present
invention as in item 7, above, wherein the (ii) one or more
polyalkoxylates is a polyalkoxylate of diethanol amine, glycerol,
pentaerythritol, a sugar alcohol, a diamine or a triamine.
9. in accordance with the aqueous compositions of the present
invention as in any of items 1, 2, 3, 4, 5, 6, 7, or 8, above,
wherein the compositions further comprise one or more coalescents,
such as glycol esters or glycol ether esters with a normal boiling
point of from 280.degree. C. to 450.degree. C. or, preferably,
300.degree. C. or higher.
10. In accordance with the aqueous compositions of the present
invention as in any one of items 1 to 9, above, wherein the aqueous
composition has a solids content of from 40 to 85 wt. % or,
preferably, from 50 to 85 wt. %, based on the total weight of the
total composition.
11. In accordance with the aqueous compositions of the present
invention as in any one of items 1 to 10, above, wherein the
aqueous composition has a volatile organic content (VOC) of 150 g/L
or less or, preferably, 100 g/L or less, or, more preferably, 50
g/L or less.
12. In accordance with the aqueous compositions of the present
invention as in any one of items 1 to 11, above, wherein the
composition further comprises one or more fillers, extenders;
preferably calcium carbonate, calcium oxide, silica, silicates;
and/or pigments, such as a white or opacifier pigment, preferably,
titanium dioxide, or, preferably, one or more pigment combined with
one or more fillers and/or extenders.
13. In accordance with another aspect of the present invention,
methods of using the aqueous compositions as in any one of items 1
to 12, above, comprise applying the aqueous compositions to a
substrate and drying, preferably, drying under ambient
conditions.
Unless otherwise indicated, conditions of temperature and pressure
are room temperature and standard pressure, also referred to herein
as "ambient conditions".
The singular forms "a," "an," and "the" include plural referents
unless the context clearly dictates otherwise.
All phrases comprising parentheses denote either or both of the
included parenthetical matter and its absence. For example, the
phrase "(meth)acrylate" includes, in the alternative, acrylate and
methacrylate.
As used herein, the term "acid monomer or anionic monomer" means
ethylenically unsaturated carboxylic acid monomer in either the
acid or anionic form (COO.sup.-).
As used herein, the term "aqueous" means water or water mixed with
up to 16 wt. %, or up to 6 wt. %, or, preferably, up to 0.5 wt. %
of a water miscible solvent which is volatile under ambient
conditions, such as a lower alkanol.
As used herein the term "ethylene oxide (EO) content" refers to the
weight percent amount determined for any polyalkoxylate by
subtracting the molecular weight of the active hydrogen compound(s)
used to make the polyalkoxylate from the number average molecular
weight of the same polyalkoxylate, dividing by the number average
molecular weight of the polyalkoxylate and multiplying the result
by 100%. For polyalkoxylates containing ethylene oxides and other
alkylene oxides, the above calculation is modified to account for
the relative amounts of ethylene oxide and the other alkylene
oxides used to make the polyalkoxylate. Thus, for example, if 2
parts ethylene oxide and 3 parts propylene oxide are used to make a
polyalkoxylate having a number average molecular weight of 1000
from ethylenediamine (fw=64), the total weight % of alkylene oxide
is (1000-64)/1000.times.100% or 93.6% and the ethylene oxide
content is .times.93.6% or 37.44 wt. %.
As used herein, unless otherwise indicated, the phrase "measured
glass transition temperature" or "measured Tg" refers to a Tg as
determined by differential scanning calorimetry (DSC), including
preheating the polymer to 120.degree. C., rapidly cooling it to
-100.degree. C., and then heating to 150.degree. C. at a heating
rate of 20.degree. C./minute while collecting data. The Tg recorded
was the midpoint of the inflection of the heat flow versus
temperature measurement curve, using the half-height method.
As used herein, unless otherwise indicated, the term "emulsion
polymer" refers to a polymer made by aqueous emulsion
polymerization.
As used herein, the term "ethylenically unsaturated carboxylic acid
monomer" refers to acrylic acid, methacrylic acid,
beta-acryloxypropionic acid, ethacrylic acid, .alpha.-chloroacrylic
acid, .alpha.-vinylacrylic acid, crotonic acid,
.alpha.-phenylacrylic acid, cinnamic acid, chlorocinnamic acid,
.beta.-styrylacrylic acid, maleic acid, itaconic acid, citraconic
acid, and salts thereof.
As used herein, the term "(meth)acrylate" means acrylate,
methacrylate, and mixtures thereof and the term "(meth)acrylic"
used herein means acrylic, methacrylic, and mixtures thereof.
As used herein, unless otherwise indicated, the phrase "weight
average molecular weight" refers to the weight average molecular
weight as measured by gel permeation chromatography (GPC) against
poly(methylmethacrylate) or poly(styrene) standards, respectively,
for an acrylic or a vinyl emulsion polymer.
As used herein, unless otherwise indicated, the term "number
average molecular weight" for a polyalkoxylate of the present
invention refers to the number average molecular weight as measured
by gel permeation chromatography (GPC) of the polyalkoxylate as a
100 microliter sample of a 0.25 wt. % solution in xylene against
polystyrene standards at 40.degree. C. using tetrahydrofuran (THF)
as eluent flowing at 1 mL/min.
As used herein, the term "pigment volume concentration" or % PVC
refers to the quantity calculated by the following formula:
.times..times..times..times..times..times..function..times..times..functi-
on..times..times..times..times..function..times..times..times..times..time-
s..times..times..times..times. ##EQU00001##
As used herein, the term "vinyl or acrylic emulsion polymer" refers
to a polymer made from one or more different monomers, such as a
copolymer, a terpolymer, a tetrapolymer, a pentapolymer etc., or
any of a random, block, graft, sequential or gradient polymer.
As used herein, the term "total polymer solids" or "polymer solids"
means the total solids of the one or more (i) emulsion polymers
and/or aqueous dispersion polymers.
As used herein, the term "solids" refers to any material that is
not volatile at 100.degree. C. Thus, the concept of solids excludes
volatile solvents, water and ammonia.
As used herein, the term "normal boiling point" refers to the
boiling point of a liquid determined at 100 kPa or atmospheric
pressure.
As used herein, the phrase "wt. %" stands for weight percent.
As used herein, unless otherwise indicated, the term "weight
average particle size" means the particle size as determined by
light scattering (LS) using a Brookhaven 90 Plus particle size
analyzer (Brookhaven Instruments Corp., Holtsville, N.Y.).
All ranges recited are inclusive and combinable. For example, a
recitation of from 2 to 15 or, preferably, from 3 to 10, or, more
preferably, from 3 to 8 poly(alkoxylate) chains means any or all of
from 2 to 15, from 2 to 10, from 2 to 8, from 2 to 3, from 3 to 15,
from 8 to 15, from 10 to 15, or, preferably, from 3 to 10 or,
preferably, from 8 to 10, or, more preferably, from 3 to 8
poly(alkoxylate) chains.
The present inventors have discovered that polyalkoxylates having
from 2 to 15 or, preferably, up to 8 polyalkoxylate chains and
having from 20 to 70 wt. % of ethylene oxide groups, based on the
weight of total polyalkoxylate solids, can make aqueous
compositions for use as paints and coatings with significant
improvements in open time and yet with little detrimental impact on
paint properties, such as film formation. The polyalkoxylate open
time additives of the present invention comprise liquids and can be
provided at 100 wt. % solids with remarkably low viscosities,
thereby enabling ease of additive handling alone or in combination
with other additives. The polyalkoxylates of the present invention
are also zero VOC materials.
The one or more polyalkoxylates (ii) of the present invention can
be represented by the formula I-[AO.sub.nH].sub.f wherein I is an
organic active hydrogen containing compound, AO is an alkylene
oxide that comprises ethylene oxide (EO) or EO combined with
propylene oxide (PO) and/or butylene oxide (BO) in a random order
or in an oligomer having blocks, preferably, at least one block of
EO, n is the total number of AO groups and may range from 1 to 50,
or, preferably, from 2 to 20; and f is the total number of active
hydrogen groups in I, which ranges from 2 to 15 or, preferably,
from 3 to 10, or, more preferably, from 3 to 8.
Suitable active hydrogen compounds I for making the polyalkoxylates
(ii) of the present invention may be chosen from diols, such as
glycols, phenols having 2 hydroxyl groups, such as cresols; and
difunctional aminoalcohols like diethanol amine; polyols having 3
or more hydroxyl groups, such as glycerol, pentaerythritol, sugar
alcohols like sorbitol, xylitol or mannitol; diamines, such as
ethylenediamine; triamines, such as diethylenetriamine; polyamines,
such as polylysine or polyethylene imines; phenolic resins having
from 2 to 15 or, preferably, from 2 to 8 or, preferably, 3 or more,
hydroxyl groups, such as hydroxyl functional phenol formaldehyde
resins; epoxy adducts of glycidyl ether with polyols; epoxy adducts
of glycidyl ethers with diamines or polyamines, such as disecondary
diamines. A sugar alcohol is considered a polyol in the present
invention.
Preferably, the active hydrogen compounds are polyols having 3 or
more hydroxyl groups, difunctional aminoalcohols, diamines,
triamines, polyamines and phenolic resins having 3 to 8 hydroxyl
groups.
The ethylene oxide (EO) content of the polyalkoxylates (ii) of the
present invention may be anywhere from 20 to 70 wt %, or,
preferably, from 20 to 50 wt. %, based on the total weight of
solids in the polyalkoxylate. The EO content should be sufficiently
large to make the polyalkoxylate water dispersible, and yet low
enough that the polyalkoxylates little enough to be compatible with
binder.
The number average molecular weight or Mn of the polyalkoxylates
(ii) of the present invention may range from 800 to 10,000 or,
preferably, 6,000 or less. Too high an Mn may result in gelling
and/or flocculation or an aqueous composition containing the
polyalkoxylate.
Examples of polyalkoxylates (i) may include, for example,
di-polyethoxylated diols like propylene glycol, tri-polyethoxylated
triols, like glycerine, polyethoxylated polyols having four or more
active hydrogen groups, such as polyethoxylated pentaerythritol,
di-, tri-, or tetra-polyethoxylated diamines, tri- or
higher-polyethoxylated polyamines, such as, penta-polyethoxylated
triethylene pentamine, and ethoxylated alkyl phenol formaldehyde
resins containing two or more poly(alkoxylate) chains.
The one or more polyalkoxylates (ii) of the present invention can
be made in a conventional fashion by reacting the active hydrogen
compound with ethylene oxide or a combination of ethylene oxide as
well as propylene oxide and/or butylene oxide.
The reaction of the active hydrogen compound with ethylene oxide to
make the polyalkoxylates (ii) of the present invention can be
carried out in a pressure reactor or autoclave at from 50 to
200.degree. C., or, preferably, from 90 to 150.degree. C. at a
pressure of from 100 to 2000 kPa. A basic catalyst may be used,
such as sodium methanolate, an alkali metal hydroxide like NaOH or
KOH.
The aqueous polymer compositions (i) of the present invention may
be chosen from aqueous dispersion polymers, such as polyurethane
dispersions and polyolefin dispersions, aqueous emulsion polymers
and mixtures thereof.
Preferably, the aqueous polymer compositions (i) of the present
invention comprise one or more emulsion polymers. Suitable aqueous
emulsion polymers may be prepared from one or more polymerizable
ethylenically unsaturated monomers, such as, for example, methyl
(meth)acrylate, ethyl (meth)acrylate, or ethylhexyl acrylate.
Suitable nonionic ethylenically unsaturated monomers for making the
emulsion polymers (i) of the present invention may, include vinyl
aromatics, such as styrene and .alpha.-methyl styrene; butadiene;
olefins; vinyl esters; vinyl halides; vinylidene chloride;
(meth)acrylonitrile; C.sub.4-C.sub.24 alkyl esters of (meth)acrylic
acid; for example, n-butyl methacrylate, 2-ethylhexyl
(meth)acrylate, and other (meth)acrylates.
Suitable polymerizable monomers for making the emulsion polymers
(i) of the present invention may further include, in copolymerized
form, from 0 to 5 wt. %, based on the total weight of monomers used
to make the polymer, of at least one multiethylenically unsaturated
monomer. Examples of multiethylenically unsaturated monomers that
may be used include allyl (meth)acrylates; glycol
di(meth)acrylates; and aromatic di- and tri-vinyl monomers, such
as, divinylbenzene, and divinyltoluene.
The emulsion polymers (i) of the present invention may further
contain, in copolymerized form, amide containing monomers, like
(meth)acrylamide, or ionic ethylenically unsaturated monomers such
as ethylenically unsaturated carboxylic acid monomers, such as
(meth)acrylic acid, itaconic acid and maleic acid.
Preferably, the emulsion polymers (i) of the present invention
comprise copolymerized ethylenically unsaturated carboxylic acid
monomers. When such acid monomers are in their deprotonated form,
as at a pH below the pKa of the acid monomers themselves, they can
be referred to as anionic monomers.
Suitable levels of copolymerized ethylenically unsaturated
carboxylic acid monomers in the emulsion polymers (i) of the
present invention may range from 0 to 10 wt. %, preferably, 0.1 to
5 wt. %, and, more preferably, 0.5 to 2.5 wt. %, based on the total
weight of monomer solids used to make the polymer.
Suitable ethylenically unsaturated carboxylic acid monomers for use
in making the emulsion polymers (i) of the present invention may
also include multi-acid functional groups that are formed from
ethylenically unsaturated monomers and that contain multiple acid
groups. The multi-acid functional groups may be incorporated into
the polymer particle, for example, by including as polymerized
units, a terminally unsaturated multiacid macromonomer.
The emulsion polymers (i) of the present invention may optionally
have one or more strong acid functional groups from monomers, in
copolymerized form, such as, for example, a phosphorus acid group,
a sulfur acid group, salts thereof, and combinations thereof. The
phosphorus acid-functional group may be a (di)hydrogen phosphate
group, phosphonate group, phosphinate group, alkali metal salt
thereof, other salt thereof, or a combination thereof. The emulsion
polymers (i) may contain such strong acid functional groups in
copolymerized form at levels ranging from 0.0 to 10 wt. %,
preferably, up to 5 wt. %, and, more preferably, up to 3.5 wt. %,
based on the weight of the monomer solids used to make the
copolymer.
Suitable phosphorus acid group containing monomers may include, for
example, (di)hydrogen phosphate esters of an alcohol containing a
polymerizable vinyl or olefinic group, such as phosphates of
hydroxyalkyl(meth)acrylates including hydroxyethyl (meth)acrylate.
Other suitable such monomers may include, for example, phosphonate
functional monomers, like vinyl phosphonic acid. Preferred
phosphorus acid monomers include phosphoethyl (meth)acrylate.
Other suitable polymerizable monomers for making the emulsion
polymers (i) of the present invention may include, for example,
hydroxy-, amine-, epoxy-, and keto-functional monomers,
autooxidizable monomers like acetoacetoxy group containing
monomers, such as acetoacetoxyalkyl (meth)acrylates, and small
amounts of adhesion-promoting monomers; as well as polymerizable
surfactants, including, but not limited to, the monomers sold as
Trem.TM. LF-40 (Henkel Corporation, King of Prussia, Pa.).
Suitable autooxidizable monomers may include, for example,
ethylenically-unsaturated acetoacetoxy group containing monomers
may include acetoacetoxyethyl methacrylate, acetoacetoxyethyl
acrylate, acetoacetoxypropyl methacrylate, allyl acetoacetate,
acetoacetoxybutyl methacrylate, 2,3-di(acetoacetoxy)propyl
methacrylate, or combinations thereof.
Preferred fast dry aqueous compositions of the present invention
may comprise one or more polyamine, which may be an emulsion
polymer. Polyamine emulsion polymers of the present invention may
be made from suitable amine containing monomers, such as, for
example, aminoalkyl vinyl ethers or sulfides; amine containing
acrylamide or (meth)acrylic esters, such as dimethylaminoethyl
(meth)acrylate; N-(meth)acryloxyalkyl-oxazolidines, such as
poly(oxazolidinylethyl methacrylate),
N-(meth)acryloxyalkyltetrahydro-1,3-oxazines, and monomers that
readily generate amines by hydrolysis, as disclosed in U.S. Pat.
No. 5,804,627.
To limit the water sensitivity of the emulsion polymers (i) of the
present invention, the total amount of phosphorus acid, multi-acid,
acid, hydroxyl, amine, ketone, aldehyde, aldol, keto-ester
(acetoacetoxy), or aldimine group functional groups in or used to
make the copolymer should not exceed 25 wt. %, or, alternatively,
should not exceed 20 wt. %.
Emulsion polymers (i) useful in the aqueous compositions of the
present invention may be prepared by conventional polymerization
processes, including suspension or emulsion polymerization at known
polymerization temperatures of from room temperature to about
90.degree. C. which may be optimized for the catalyst system
employed. The emulsion polymers may have a unimodal or a
multimodal, including a bimodal, particle size distribution.
Suitable emulsion polymerization techniques are well known in the
polymer arts, and may include single stage processes and multiple
stage polymerization processes. In the latter case, the first stage
polymer can be prepared by various techniques, such as solution
polymerization, bulk polymerization or emulsion polymerization.
Preferably, emulsion polymerization is used.
The emulsion polymerization techniques used for preparing
multi-stage polymer particles are well known in the art and are
disclosed, for example, in the U.S. Pat. Nos. 4,325,856, 4,654,397
and 4,814,373. Polymerization may be carried out using one or more
water-soluble or water-insoluble polymerization initiators which
thermally decompose(s) at the polymerization temperature to
generate free radicals, such as, for example, persulfates, like
ammonium or alkali metal (potassium, sodium, or lithium)
persulfate.
Emulsion polymerization initiators may be used alone or as the
oxidizing component of a redox system, which also includes a
reducing component, such as, for example, ascorbic acid or sodium
formaldehyde sulfoxylate. Examples of redox catalyst systems
include t-butyl hydroperoxide/sodium formaldehyde
sulfoxylate/Fe(II), and ammonium persulfate/sodium bisulfite/sodium
hydrosulfite/Fe(II). The initiator and the optional reducing
component may be used in proportions from 0.001% to 5% each, based
on the weight of the ethylenically unsaturated monomers in the
monomer mixture to be polymerized. Accelerators such as chloride
and sulfate salts of cobalt, iron, nickel, or copper may be used in
small amounts.
Chain transfer agents, such as mercaptans, polymercaptans, and
polyhalogen compounds, including alkyl mercaptans such as n-dodecyl
mercaptan, may be used to control the molecular weight of emulsion
polymers of the present invention. Amounts of these may range from
0 to 10 wt. %, based on the total weight of the ethylenically
unsaturated monomers used to prepare a vinyl or acrylic emulsion
polymer.
Suitable emulsion polymers (i) of the present invention may
contain, as polymerized functional groups, those that are anionic
when deprotonated, up to 10 wt. %, for example, up to 7.5 wt. %,
and, preferably, 0.1 wt. % or more, or, preferably, up to 5.0 wt.
%, of one or more ethylenically unsaturated carboxylic acid
monomer, such as a, carboxylic acid, carboxylic anhydride,
phosphorus acid group containing monomers, sulfur containing acid
monomers, and mixtures thereof.
Aggregation of the aqueous polymer compositions (i) of the present
invention may be discouraged by including a stabilizing surfactant
in the polymerization mixture in the polymerization vessel. M any
examples of surfactants suitable for emulsion polymerization are
given in McCutcheon's Detergents and Emulsifiers (MC Publishing
Co., Glen Rock, N.J.), published annually. Other types of
stabilizing agents such as protective colloids, may also be used.
For example, methyl cellulose and hydroxyethyl cellulose may be
included in the polymerization mixture.
The aqueous polymer compositions (i) of the present invention may
be prepared as an aqueous dispersion or suspension with a solids
level of from 20 to 70 wt. %, or, preferably, in the range of from
30 to 60 wt. %.
Preferably, the compositions of the present invention comprise high
solids aqueous polymer compositions, elastomeric aqueous polymer
compositions or fast dry aqueous polymer compositions.
Preferably, the aqueous compositions of the present invention may
have very high total solids contents of from 50 to 85 wt. %, or up
to 80 wt. %. Such compositions tend to be fast drying.
Suitable fast dry compositions may include one or more polyamines
in compositions that have a pH of from 7 to 11.5 or, preferably, 8
or higher.
The aqueous compositions of the present invention may comprise one
or more filler, extenders and/or pigments, even if the compositions
are not coating compositions, for example, if the compositions are
non-cementitious binder compositions, such as may be used for
waterproofing membranes or EIFS topcoats. Suitable concentrations
of fillers, extenders and/or pigments in fast dry compositions may
range from 50 to 90 wt. % or, preferably, from 60 to 85 wt. %, of
total solids. Such compositions may have low total polymer solids
proportions of from 10 wt. % to 40 wt. %, or, preferably, 15 wt. %
or more, or, preferably, up to 25 wt. %, all wt. % s based on the
total weight of the aqueous compositions.
The aqueous compositions of the present invention may have, for
example, a percent pigment volume concentration (% PVC) of from 0
to 80%, or 20% or higher, or, preferably, from 40 to 75%, or, more
preferably, 40% or more or up to 65%. The compositions having a %
PVC of 40% or more may be high solids compositions.
Suitable fillers or extenders for use in the aqueous compositions
of the present invention may include, for example calcium
carbonate, silicas, silicates, like dolomite or aluminum silicates,
talcs, nepheline syenite, ceramics like calcium oxide, quartz(ite),
glass or polymeric microspheres, cement, and silica sand. Preferred
is calcium carbonate and silicates.
In the aqueous compositions of the present invention, silica may be
used at from, 0 to 40% PVC, preferably 0 to 25% PVC; nepheline
syenite or other aluminum silicates may be used 0 to 40% PVC,
preferably 0 to 25% PVC.
Suitable pigments for use in the aqueous compositions of the
present invention may include titanium dioxide, organic pigments,
carbon black and iron oxides. Inorganic pigment amounts may range
from 0 to 15% PVC, preferably, from 3 to 10% PVC.
Opaque polymers as pigments may be used at from 0 to 30% PVC, or,
preferably to 0 to 15% PVC. Opaque polymers are considered pigment
and not binder for % PVC calculations.
The aqueous compositions of the present invention may contain
additional ingredients, such as, for example, surfactants,
dispersants, thickeners, such as polyvinyl alcohol (PVA),
hydroxyethyl cellulose (HEC), associative thickeners, such as, for
example, hydrophobically-modified, alkali soluble emulsions (HASE),
hydrophobically-modified ethylene oxide-urethane polymers (HEUR),
and hydrophobically-modified hydroxy ethyl cellulose (HMHEC),
alkali-soluble or alkali-swellable emulsions (ASE), other
cellulosic thickeners, and attapulgite clay; rheology modifiers;
silanes, colorants; coalescents and plasticizers; crosslinking
agents; tackifiers; dispersants; wetting agents; dyes; sequestering
agents; preservatives, biocides and mildewcides; anti-freeze
agents; slip additives; waxes; defoamers; corrosion inhibitors;
anti-flocculants; and ultraviolet light absorbers, such as
benzophenone. HEC is the preferred thickener.
Suitable dispersants for use in the present invention may include
one or more non-ionic, or anionic dispersants, such as, for
example, carboxylic acids, and anionic polymers such as
homopolymers and copolymers based on polycarboxylic acids,
including those that have been hydrophobically- or
hydrophilically-modified, e.g. poly(meth)acrylic acid with various
comonomers such as styrene, or alkyl(aryl) (meth)acrylate
esters.
One or more surfactants may be used to stabilize an aqueous
emulsion polymer composition after polymerization of monomers or in
the formation of polymer dispersions and may be present at levels
of from 0.1 to 8 wt. % based on the total weight of monomer in
polymerization. Suitable surfactants include cationic, anionic, and
non-ionic surfactants.
The aqueous compositions of the present invention may comprise from
0.1 to 5 wt. % or, preferably, from 0.1% to preferably up to 2 wt.
%, based on the total weight of solids in the composition, of a
coalescent. A coalescent may comprise, for example, any ingredient
that facilitates the film formation of an aqueous polymeric
dispersion, such as by lowering the minimum film forming
temperature ("MFFT") of the composition as measured according to
ASTM International Publication ASTM D 2354-10 (2010, ASTM
international, West Conshohocken, Pa.), West Conshohocken, Pa.
Suitable coalescents may comprise glycol esters or glycol ether
esters with a normal boiling point of at least 280.degree. C.
Suitable coalescents may be, for example, any compound according to
Formula Z, below:
##STR00001##
wherein R.sub.1 is a C.sub.1 to C.sub.8 alkyl group, phenyl or
benzyl; wherein R.sub.2 is either hydrogen or methyl; wherein
R.sub.3 is a C.sub.4 to C.sub.6 alkyl group or phenyl; and wherein
n=2-4, with the proviso that R.sub.1 is C.sub.5-C.sub.8 when
R.sub.3 is phenyl and n=2-4. R.sub.3 can also be an alkyl group
bearing a keto group such as the one in levulinic acid.
Non-inclusive examples of glycol ether esters described by this
formula are diethylene glycol phenyl ether benzoate, tripropylene
glycol methyl ether benzoate, dipropylene glycol phenyl ether
levulinate, and tripropylene glycol n-butyl ether isopentanoate.
Other suitable coalescents are the dibutoxy adipates of Formula A,
below.
##STR00002##
wherein R.sub.1 and R.sub.4 are C.sub.1 to C.sub.8 alkyl groups,
phenyl or benzyl; wherein R.sub.2 is either hydrogen or methyl;
wherein n=1-4; wherein R.sub.3 is a carbon chain containing 0 to 4
carbon atoms and may contain a double bond. Non-inclusive examples
of bis-glycol ether esters described by this formula are
bis-dipropylene glycol n-butyl ether adipate, bis-diethylene glycol
n-butyl ether malonate, bis-diethylene glycol n-butyl ether
succinate, and bis-dipropylene glycol n-butyl ether maleate. Such
coalescents can be prepared as disclosed in U.S. Patent Publication
No. 2012/0258249A, to Adamson et al.
Still other suitable coalescents are propylene glycol phenyl ether,
ethylene glycol phenyl ether, dipropylene glycol n-butyl ether,
ethylene glycol n-butyl ether benzoate, tripropylene glycol n-butyl
ether, TEXANOL.TM. 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate
(Eastman Chemical, Kingsport, Tenn.), Optifilm.TM. Enhancer 400
triethylene glycol bis-2-ethylhexanoate (Eastman), tributyl
citrate, and/or glycol ether ester-compounds, such as those
disclosed in U.S. Patent Publication No. 2012/0258249A, to Adamson
et al.
The compositions of the present invention may further include one
or more silanes, such as, e.g. oxysilanes, amino alkoxy silanes or
epoxy alkoxy silanes.
Preferably, the one or more silanes comprises an amino silane or a
diamino silane, or, more preferably a hydrolysable amino silane or
diamino silane. Examples of such preferred silanes may include, for
example, N-ethylaminopropyltrimethoxy silane,
aminoethylaminopropylmethyldimethoxy silane, aminoethylaminopropyl
trimethoxy silane, aminopropylmethyldimethoxy silane,
aminopropyltrimethoxy silane, such as those available from Dow
Corning, Midland, Mich., Hulls of America, Piscataway, N.J., or
Wacker Silicones Corporation, Adrian, Mich. One example is an
aminoethylaminopropyltrimethoxy silane sold under the tradename Dow
Corning Z-6020. Other suitable silanes may include, for example,
oligomeric aminoalkylsilanes and polymeric aminoalkylsiloxanes.
The aqueous compositions of the present invention include water or
water having dissolved therein a low VOC water miscible organic
solvent, such as methanol, ethanol and glycol ether. Water is
preferred.
The aqueous compositions of the present invention may be used in
architectural and industrial coatings, roof coatings,
non-cementitious mortars, waterproofing membranes and exterior
insulation finishing systems (EIFS). Various applications methods
are known in the art, including spraying the composition on
substrate. Other methods include applying the composition by hand
using a trowel, paint brush or a paint roller. Coatings may be
applied in one or more layer.
The compositions are suitable for coating or forming films on
substrates such, as, for example, wood, metal or industrial
substrates, building substrates and roadways; and find use in
exterior insulation finishing systems (EIFS), walkways, runways,
parking areas, and indoor floors (such as in factories or shopping
malls). Typical building substrates include, for example, drywall,
wood, plywood, masonry, concrete, cement, stone, stucco, tile, and
combinations thereof; metals may include aluminum, stainless steel,
or carbon steel; roadways include, for example, tar, asphalt,
masonry, concrete; other substrates may include resins or polymeric
materials. All of the substrates may already have one or more
layers of an existing coating or paint which may be fresh or
aged.
EXAMPLES
The following examples illustrate the present invention.
Abbreviations used in the Examples include: BA=butyl acrylate;
MMA=methyl methacrylate; MAA=methacrylic acid; nDDM=n-dodecyl
methacrylate; EHA=ethylhexyl acrylate; STY=styrene; BMA=butyl
methacrylate; MPG=monopropylene glycol; DETA=diethylene triamine;
DAnMDPA=3,3' diamino-N methyl dipropyl amine
Also used in the Examples are:
Acrylic emulsion polymer A (50 wt. % solids, one stage, BA/MMA
emulsion polymer, Tg (DSC)<5.degree. C.);
Acrylic emulsion polymer B (50 wt. % solids, single stage, acid
functional BA/MMA emulsion polymer, Tg (DSC) .about.25.degree.
C.);
Acrylic acid copolymer dispersant (Tamol.TM. 165A, 21.50 wt. %
solids, Dow);
Dioctyl sulfosuccinate surfactant (Triton.TM. GR-7M, Dow, 100 wt. %
solids);
Mineral oil/silica defoamer (Drewplus.TM. L-475, Ashland Chemical,
Houston, Tex., 100 wt. % solids);
Glycol ether ester coalescent DPnB Adipate (Dipropylene glycol
butyl adipate 100 wt. % solids); and,
Triethylene glycol bis-2-ethylhexanoate (Optifilm.TM. 400
coalescent, Eastman Chemicals).
Additives for open time of the invention are characterized in Table
1, below:
TABLE-US-00001 TABLE 1 Poly (alkoxylates) additives of the
invention Active EO Example Hydrogen I Functionality, f wt % Mn 1
Glycerine 3 32 4500 2 Diol (MPG 2 40 2500 monopropylene glycol) 3
Di-Ethylene 5 25 5000 Triamine 4 DAnMDPA 4 15 6800 (amine) 5 Alkyl
Phenol 6-8 23 3700 Formaldehyde resin
The additives in Table 1, above, were added at 2 wt. %, based on
the weight of the total formulation shown in Table 2, below, into
the letdown, to make an aqueous paint composition.
TABLE-US-00002 TABLE 2 Coating composition 22% PVC and a volume
solids of 36% Wt. Material Name parts Grind Rutile TiO.sub.2 slurry
(76.5 wt. % solids in water, Ti-Pure .TM. 1584.45 R-746, Chemours,
Wilmington, DE) Polyacrylic acid dispersant (25 wt. % in water,
Tamol .TM. 731A, 33.97 Dow) Polyether siloxane surfactant (BYK 348,
Byk Additives, Inc., 4.53 Louisville, KY) Polyether siloxane
defoamer (Tego Foamex .TM. 810. Evonik 2.26 Industries, Parsippany,
NJ) Grind Sub-total 1625.22 Premix Water 94.67 Acrylic emulsion
polymer A 2374.41 Ammonia (28%) 3.17 BYK 348 surfactant 4.53 Tego
Foamex .TM. 810 defoamer 2.26 Acrysol .TM. RM-2020 NPR
Hydrphobically modified ethoxylated 138.15 urethane (HEUR) rheology
modifier (Dow) Acrysol .TM. RM-8W (HEUR rheology modifier, Dow)
19.48 Water 549.44 Premix Sub-total 3186.11 Totals 4811.33 Property
Value Total % PVC 21.95 Volume Solids 36.44
The formulations were tested, as follows:
Open time: The indicated composition in a container was drawn down
on Leneta chart (B#4425 paper, Leneta company, Inc., Mahwah, N.J.)
with a 125 micron (5 mil) square bar that is 10 cm (4'') wide.
Immediately after the drawdown was complete, a timer was started at
0 minutes. With a tongue depressor, two (2) parallel lines were
drawn from the edge of the chart and running 1/3 of the length of
the chart. A brush (2.54 cm nylon brush, Wooster model 4176,
Wooster Brush Company, Wooster, Ohio) was dipped in the composition
and brushed out on scrap paper. The container with the indicated
composition was placed on a scale. Then, starting at the 1 minute
time mark and repeating every min. thereafter, the brush was loaded
so that from 1 to 2 cm (1/2 in.-3/4 in.) of the bristles of the
brush were dipped into the composition in the container so as to
hold the desired amount of 0.6-0.7 gms of the composition on the
brush, as determined by weighing the container on the scale. The
loaded brush was placed down on the left side of the drawdown and
brushed in a back and forth manner across the two scribed lines of
the painted Leneta chart. Each stroke was counted as 1 (back and
forth=2). In each minute, this was repeated until 20 strokes were
completed; the brushing time was 30 seconds within each minute.
This was continued every minute until "failure" was observed
visually. Failure means the scribed lines did not disappear after
brushing. The time for such failure was recorded as the open time
of the composition. An average from a total of three trials of this
experiment was taken for each Example indicated and the results
were recorded as the open time of the composition in Table 3,
below.
TABLE-US-00003 TABLE 3 Open Time Additive Performance: Example Open
time (mins) 1 12 2 16 3 13 4 7 5 7 6* (No 4 additive) *Denotes
Comparative Example
As shown in Table 3, above, aqueous coating compositions with the
open time additives of the present invention dramatically improved
the open time of the aqueous compositions. The open time was
especially improved when using polyalkoxylates of glycerol,
propylene glycol and polyamines as in Examples 1, 2 and 3.
The additives in Table 5, below, were added to the letdown in the
amounts indicated in Table 4, below, based on the total solids
weight of the formulation, to make an aqueous paint
composition.
TABLE-US-00004 TABLE 4 Coating composition 23% PVC and a volume
solids of 35% wt. parts [[not Material Name pounds]] Grind Rutile
TiO.sub.2 slurry (76.5 wt. % solids in water, Ti-Pure .TM. 341.31
R-746, Chemours, Wilmington, DE) Water 58.06 Acrylic acid copolymer
dispersant 8.70 Dioctyl sulfosuccinate surfactant 2.11 Grind
Sub-total 410.18 LetDown Mineral oil/silica defoamer 2.01 Acrylic
emulsion polymer B 494.80 Coalescent or Additive blend (see Table
5, below) 19.79 water 106.01 Acrysol .TM. RM-2020 NPR
Hydrophobically modified 20.05 ethoxylated urethane (HEUR) rheology
modifier (Dow) Acrysol .TM. RM-8W (HEUR rheology modifier, Dow)
5.31 LetDown Sub-total 647.97 Totals 1058.15
TABLE-US-00005 TABLE 5 Effect of Coalescent on Open Time Open time
Example Composition (mins) 7* Acrylic emulsion polymer B -- 8*
triethylene glycol bis-2-ethylhexanoate (1.8 wt. 7-8 %) 9
triethylene glycol bis-2-ethylhexanoate (1.8 wt. 18-19 %) + 1.13
wt. % Open time Additive of Example 2 10* DPnB Adipate (1.8 wt. %)
9 11 DPnB Adipate (1.8 wt. %) + 0.68 wt. % Open 11-12 time Additive
of Example 2 12 DPnB Adipate (1.8 wt. %) + 1.13 wt. % Open 15-16
time Additive of Example 2 13 DPnB Adipate (1.8 wt. %) + 1.35 wt. %
Open 16-17 time Additive of Example 2 14 DPnB Adipate (1.8 wt. %) +
1.13 wt. % Open 12 time Additive of Example 2 premixed before
addition
As shown in Table 5, above, the aqueous compositions of the present
invention improve open time relative to compositions just
containing a coalescent, as in Comparative Examples 8 and 10. The
open time is improved more where more of the open time additive is
used. Compare Examples 11, 12 and 13 to Comparative Example 10.
* * * * *